What happens if I miss the deadline for filing a priority claim in a U.S. patent application?

If you miss the deadline for filing a priority claim in a U.S. patent application, you may still have options, but they are limited:

• Petition for Unintentional Delay: You can file a petition to accept an unintentionally delayed priority claim under 37 CFR 1.55(e). This petition must be filed within the later of four months from the actual filing date of the application or sixteen months from the filing date of the prior foreign application.
• Continuation-in-Part (CIP) Application: If the deadline has passed and you can’t file a petition, you might consider filing a CIP application, which allows you to claim priority to the earlier application while also adding new matter.
• Consequences: Failing to properly claim priority can affect the patent’s validity and enforceability, particularly if prior art emerges in the intervening period between the foreign filing and the U.S. filing.

As stated in MPEP 214.01: “The claim for priority must be filed within the later of four months from the actual filing date of the application or sixteen months from the filing date of the prior foreign application in an original application filed under 35 U.S.C. 111(a).”

To learn more:

• priority claim
• deadline
• unintentional delay
• petition
• CIP application

To learn more:

• unintentionally delayed claim